A Phase III, Multicenter, Randomized, Double-Blind, Placebo Controlled, Comparative Trial of AMD3100 (Plerixafor)+G-CSF vs. Placebo+G-CSF in Non-Hodgkin’s Lymphoma (NHL) Patients for Autologous Hematopoietic Stem Cell (aHSC) Transplantation.
Abstract AMD3100, Plerixafor (A)+G-CSF (G) have safely and effectively allowed aHSC mobilization in Phase I and II studies. This Phase III, multicenter, randomized, double-blind, placebo controlled study compared the safety and efficacy of A+G versus Placebo (P)+G to mobilize and transplant patients with NHL. Methods: Adult NHL patients requiring an aHSC transplant, in first or second CR or PR were eligible to participate. Patients received G (10μg/kg/day) subcutaneously (SQ) for 4 days. On the evening of Day 4, patients received either A (240μg/kg SQ) or P. Patients underwent apheresis on Day 5 after an AM dose of G and 10–11 hours after administration of study treatment. Patients continued to receive the evening dose of study treatment, followed by AM dose of G and apheresis for up to a total of 4 aphereses or until ≥5 x 106 CD34+cells/kg were collected. Only study cells were used for transplant. Patients who failed to mobilize ≥2 x 106 CD34+cells/kg could enter into a rescue arm of A+G, without unblinding of randomized treatment. The primary endpoint was the percentage of patients who achieved ≥5 x 106 CD34+cells/kg in 4 or less aphereses days. All patients will be followed for ≥12 months post-transplant. Results: 298 patients were enrolled and randomized. All patients have completed 100 days follow-up and are included in this intent-to-treat analysis. Baseline characteristics were similar between groups. The primary endpoint was met in 89/150 (59%) patients in the A+G group and 29/148 (20%) patients in the P+G group, p<0.0001. 130/150 (87%) patients in the A+G group and 70/148 (47%) patients in the P+G group collected ≥2 x 106 CD34+cells/kg in 4 or less aphereses days, p<0.0001. Kaplan-Meir Estimates of Time to Trget Collection of ≥ × 106 CD34 + cells/kg Kaplan-Meir Estimates of Time to Trget Collection of ≥ × 106 CD34 + cells/kg The figure shows that more patients in the A+G group reached target after 1 day of apheresis than patients in the P+G group after 4 days of apheresis. A+G rescue was successful in 33/52 rescue patients in the P+G group and 4/10 rescue patients in the A+G group. 135 patients (90%) in A+G group and 82 patients (55%) in P+G group underwent transplantation. Median time to engraftment was Day 10 for PMN and Day 20 for platelets in both groups. Through 100 days, grafts were durable in all but 2 A+G (133/135) patients and in all P+G (82) patients. A+G patients experienced a higher incidence of GI effects (mild to moderate) and injection site erythema than P+G patients. There were 2 drug related serious adverse events in the A+G group and 1 in the P+G group. Conclusions: In this study, the addition of AMD3100 to G-CSF is generally safe and well tolerated and is superior to G-CSF alone for aHSC mobilization in NHL patients. A+G patients were statistically significantly more likely to achieve target cell collection quicker and to achieve sufficient cells for successful transplant than P+G patients.
Successful Stem Cell Mobilization Rescue by AMD3100 (Plerixafor)+G-CSF for Patients Who Failed Primary Mobilization: Results from the Phase III (3101-NHL) Study.
Abstract Background: AMD3100 (plerixafor)+G-CSF (A+G) was generally safe and more effective in mobilizing CD34+ hematopoietic stem cells compared to placebo+G-CSF (P+G) in a Phase III, multicenter, randomized, double-blind, placebo controlled study conducted in patients with non-Hodgkin’s lymphoma (NHL). In the intent-to-treat analysis, 78/148 (53%) patients in the P+G group and 20/150 (13%) patients in the A+G group failed to mobilize ≥ 2 x 106 CD34+ cells/kg, p<0.0001. Of these failure patients, 52 in the P+G group and 10 in the A+G group consented to enter into the rescue arm of the study. This abstract reports the outcomes of these rescue patients. Methods: Patients enrolled in the Phase III study who failed to mobilize ≥2 x 106 CD34+ cells/kg could enter into the rescue arm of the study and receive A+G. The patient’s treatment assignment in the study remained blinded. Following a rest period of ≥7 days, patients were given G (10 μg/kg/day) subcutaneously (SQ) for 4 days. In the evening around 10PM on Day 4, patients were given a dose of A (240 μg/kg SQ). On Day 5, all patients returned to clinic to receive a morning dose of G before apheresis. Patients continued to receive the evening dose of A followed by morning dose of G and apheresis the next day for up to a total of 4 aphereses or until ≥5 x 106 CD34+ cells/kg were collected. Pooled cells were allowed for transplantation. Results: After rescue therapy, 33/52 (63%) patients who previously failed P+G and 4/10 (40%) patients who previously failed A+G collected ≥2 x 106 CD34+ cells/kg. Seven of the 33 patients who previously failed with P+G collected ≥ 5 x 106 CD34+ cells/kg. Six of the ten A+G patients and 46/52 P+G patients were transplanted. Median time to PMN engraftment was Day 10 and Day 11 for the A+G and P+G groups, respectively. Median time to platelet engraftment was Day 22 and Day 20 for the A+G and P+G groups, respectively. One patient in the P+G group never had platelet counts > 50,000 and was counted as a failure to engraft, even though the patient was clinically stable through 6 months post-transplant. In the re-mobilized group, 9 patients died (2 patients were never transplanted and 7 patients had disease progression). Grafts were durable for ≥100 days in all 6 rescued A+G patients and all 41 rescued P+G patients who engrafted. The predominant adverse events were mild gastrointestinal effects (diarrhea, nausea, vomiting, and abdominal pain) and injection site reactions. There were no drug-related serious adverse events reported in these re-mobilized patients. Conclusions: The addition of AMD3100 to G-CSF successfully mobilized sufficient stem cells for transplant in 63% of NHL patients who previously failed mobilization with G-CSF alone. The high success rate is consistent with the Compassionate Use Protocol experience. AMD3100 was generally well tolerated. The 40% success rate in the patients who previously failed AMD3100+G-CSF suggests that re-mobilization with the same combination is a potentially useful strategy for similar patients.